

package com.hazelcast.internal.metrics.metricsets;

import com.hazelcast.internal.metrics.MetricsRegistry;

import java.lang.management.ClassLoadingMXBean;
import java.lang.management.ManagementFactory;

import static com.hazelcast.internal.metrics.MetricDescriptorConstants.*;
import static com.hazelcast.internal.metrics.ProbeLevel.MANDATORY;
import static com.hazelcast.internal.util.Preconditions.checkNotNull;

/**
 * A Metric set for exposing {@link java.lang.management.ClassLoadingMXBean} metrics.
 */
public final class ClassLoadingMetricSet {

    private ClassLoadingMetricSet() {
    }

    /**
     * Registers all the metrics in this metric pack.
     *
     * @param metricsRegistry the MetricsRegistry upon which the metrics are registered.
     */
    public static void register(MetricsRegistry metricsRegistry) {
        checkNotNull(metricsRegistry, "metricsRegistry");

        ClassLoadingMXBean mxBean = ManagementFactory.getClassLoadingMXBean();

        metricsRegistry.registerStaticProbe(mxBean, CLASSLOADING_FULL_METRIC_LOADED_CLASSES_COUNT, MANDATORY, ClassLoadingMXBean::getLoadedClassCount);

        metricsRegistry.registerStaticProbe(mxBean, CLASSLOADING_FULL_METRIC_TOTAL_LOADED_CLASSES_COUNT, MANDATORY, ClassLoadingMXBean::getTotalLoadedClassCount);

        metricsRegistry.registerStaticProbe(mxBean, CLASSLOADING_FULL_METRIC_UNLOADED_CLASSES_COUNT, MANDATORY, ClassLoadingMXBean::getUnloadedClassCount);
    }
}
